What I found was exactly the same, small amounts of a bland food many times a day and gradually increase the amount. I see you are keeping in touch with the vet so that is good. Here is another thread from Yt that happened to come up on google, I didn't have time to read it all but there may be something in there about food and other things that might help.
http://www.yorkietalk.com/forums/sic...creatitis.html